1. Field of Invention
The invention relates to the structure of a TFT (Thin Film Transistor) LCD (Liquid Crystal Display) and the method for making the same. More particularly, the invention relates to the structure of an organic light-emitting material TFT LCD and the method for making the same.
2. Related Art
The light-emitting methods in the existing TFT LCD's can be classified as active and passive ones. Early light-emitting methods are all passive. A backlight source is used at the back of a glass substrate as the light source. A TFT IC (Integrated Circuit) on the glass substrate is used to control the liquid crystal layer between the glass substrate and a transparent conductive glass, so that the liquid crystal layer becomes transparent or opaque. Afterwards, the light passing through the liquid crystal layer is further filtered by color filter plates so that the emitted light can be red, green or blue. Through signal processing, light beams of three different colors are mixed to produce colorful images. This kind of passive light-emitting methods requires the use of a backlight source and the opening of the LCD has to be adjusted to obtain better light intensity.
With continuous researches and development in light-emitting materials, using light-emitting materials as the light sources of TFT LCD's becomes the trend in modern technologies. Using light-emitting organic materials as the light source in the TFT LCD and using TFT's to control the light-emitting material or the driving circuit for providing a voltage to the light-emitting material can easily control the bright spots on the LCD. The structure and manufacturing method for TFT LCD's can thus be greatly simplified.
The industry has developed mature technologies in producing red, blue and green organic light-emitting materials. Not only can they be used on an LED (Light-Emitting Diode) body, they can also be used as the light source of TFT displays. Since using organic light-emitting materials as the light sources of TFT displays only requires the use of the photolithographic and etching procedures to define the pattern on an organic light-emitting material layer, the yield can be effectively increased without being limited by the liquid crystal layer.
Therefore, it is desirable to have a new structure of TFT LCD, which uses red, blue and green light-emitting organic materials as the light source of the LCD and produces colorful images using a photo mask pattern. Furthermore, a manufacturing method for making the above-mentioned light source is proposed to more effectively assemble the LCD's.